Developement of high precision visualization system for high intensity particle beams

本研究的目的是开发能够测量粒子轨迹并在高速环境下将其可视化的探测器系统。为此，我们(1)建造了0.5 mm的多线正比室并研究了它的性能，(2)设计并制作了32路MWPC紧凑型前置放大系统，(3)制作了0.5 mm间距的硅条探测器系统，研究了该系统在高辐射剂量下的工作情况。我们已经使用2.5 mm漂移室进行了各种高强度次级光束的实验。然而，由于我们正在进入具有更高束流强度的次级粒子束的新阶段，开发高分辨率的跟踪装置是非常重要的。与2.5 mm漂移室相比，0.5 mm MWPC的每根线的计数速率将减少一个数量级，因此可以处理10倍以上的粒子强度。用Ar-异丁烷气体对0.5 mm MWPC进行了测试，发现该电离室呈现出合理的平台，与魔力气体混合时工作得很好。此外，基于4通道放大器-整形-鉴别器芯片，开发了一种新的32路前置放大器，其密度是原来的两倍。该读出系统具有良好的性能，高集成度的读出系统现已投入使用。此外，还成功地研制了一个0.5 mm间距的SSD，该SSD与3片48路前置整形鉴别器ASIC芯片集成在一起，并作为电子能谱仪的焦平面探测器系统。

The aim of the present study is to develop detector systems capable of measuring particle tracks and visualize them under high rate environment. To this end, we have(1) constructed 0.5 mm multiwire proportional chamber and investigated its performance,(2) designed and fabricated 32 ch compact preamplifier system for MWPC and,(3) fabricated 0.5 mm pitch silicon strip detector system and studied to what extent the system works under high radiation dose.We have been using 2.5 mm drift chamber for various experiments with high intensity secondary beams such as pions and kaons. However, since we are entering into the new phase that secondary particle beams with much higher beam intensity are available, it is very important to develop high resolution tracking devices. Compared with the 2.5 mm drift chamber, the 0.5 mm MWPC will have one order of magnitude less count rate per wire, thus can handle 10 times higher particle intensity. Yet, it will give us better position resolution.The 0.5 mm MWPC was tested with Ar-Isobutane gas and it was found the chamber present reasonable plateau and works quite well with the magic gas mixture.In addition, a new 32 ch preAmplifier which has twice density was developed based on 4 ch Amplifier-Shaper-Discriminator chips. It showed good performance and the high-integration read-out system is now ready for use.Furthermore, a 0.5 mm pitch SSD which are integrated with the three 48 ch-preAmp-shaper-discriminator ASIC chips has been successfully developed and it has been used as a focal plane detector system of the electron spectrometer.